1. Field of the Invention
The present invention relates to a method for manufacturing compressed fibrous molded articles used in automobile construction, apparatus for carrying out the method and the compression molded articles formed by the method and apparatus. More particularly, fibers, binder agents and additives are fed by means of a first device into a feed passage, in which the infed material components are deposited by means of a second device in such a manner as to form a molded article blank on a conveyor device. The molded article blank is deposited on a conveyor device to a heating device, where the molded article blank is predried and the binding agent is condensed by a heat treatment, in order subsequently to be molded into a parison blank in a parison mold. The partially formed blank is placed in a compression mold and a compression molded article is produced from the partially molded blank.
2. Description of the Prior Art
The aforementioned method and devices are used essentially in the automobile industry which applies such compression molded articles to inside fittings of vehicles. The good sound and heat insulating properties of these fibrous molded articles are especially valuable for this type of use. To correctly fulfill the specific geometric, acoustic and strength requirements, these molded articles may include regions with inherently different thicknesses and identical densities or identical thicknesses and different densities.
In the known methods, the materials to be processed are deposited uniformly on a conveyor belt, in order to temporarily produce a non-woven fabric having uniform thickness and uniform density. This prefabricated non-woven fabric is subsequently fed through a contouring device, in which the desirable relief shapes are cut out, milled out, sawn out of and/or removed by suction from the non-woven fabric. Compression molded articles anticipating the aforementioned requirements can be produced with this contouring treatment of the nonwoven fabric.
However, these known methods have various drawbacks. For example, great quantities of waste scraps are produced by the known contouring treatment, which are generally not recycled, since the manufacture of the nonwoven fabrics and the manufacture of the compression molded articles are undertaken in operations independent of one another.
Also, modification of the contouring tools is required each time a new contour is to be shaped, whether the tools are cutting rollers, contouring blades or milling head arrangements. These tool modifications are expensive and therefore the compression molded articles must always be manufactured in large quantities and more problematical storage requirements must be taken into consideration.